Physical Activity and Nutrition for Health

Cardiovascular disease is the leading cause of death in the United States. Research has identified several factors that contribute to the risk for cardiovascular disease including obesity, inactivity, elevated blood lipids, and a diet high in fat and cholesterol.  The most recent National Health and Nutrition Examination Surveys data (2003-2006) showed that for children aged 6-11 years and 12-19 years, the prevalence of overweight was 17.0% and 17.6% respectively. 

Young children with high blood cholesterol levels often continue to have elevated blood lipids into adulthood, increasing their risk for cardiovascular disease. However, research has shown that when serum cholesterol levels are reduced, the risk of cardiovascular disease is also reduced. Because cardiovascular disease is thought to develop beginning in childhood, programs aimed at reducing risk factors in children can result in lifelong benefits. 

The ideal setting for promoting heart-healthy behaviors among children is within schools. School-based cardiovascular health education has been shown to result in improved heart health knowledge, attitudes, and behaviors. However, since the family is also a primary influence on children's health habits, the effectiveness of school-based programs may be increased through the support and education of parents as role models for healthy behaviors.

Physical Activity and Nutrition for Health is a 20-week school-based nutrition and exercise program for elementary school-aged children that includes a family support component. The curriculum and guided home activities provide specific practice in using skills to modify behaviors that are considered risk factors for cardiovascular disease. 

In the intervention schools, students receive physical education instruction for three 30-minute lessons per week. Lessons include a variety of cooperative activities and games with 20 minutes of aerobic activity in each. Children receive suggestions on how to participate in activities such as walking and bicycling with their parents. Nutrition education is scheduled as part of the classroom curriculum for two 30-minute lessons per week. The students are given packets at the beginning of each week, to be returned the following week, containing information and suggested activities to complete with their families. 

The program consists of five 30-minute sessions per week over a 20-week period, including three physical education sessions and two nutrition education sessions each week. For the study, teachers received 10 hours (1 hour per week) of training before program implementation. 

The primary audience for the Physical Activity and Nutrition for Health intervention is elementary school-aged children (grades 3 and 4). 

The Physical Activity and Nutrition for Health program is designed to be integrated into an existing school curriculum, supplemented with guided home activities.

The Physical Activity and Nutrition for Health teachers' manual, "Health-Related Fitness for Grades 3 and 4."

This study took place over 10 weeks in the fall semester and 10 weeks in the spring semester and involved teachers, parents, and third-grade students from six elementary schools (three intervention and three control schools) in Humboldt County, California.  Prior to the start of the intervention, informed consent was obtained from all participating children and their parents. 

Pretests were administered to students in both the intervention and control schools in the fall, at the start of the intervention. Students were evaluated for height, weight, body mass index (BMI), body fat, blood cholesterol, time to run 1 mile, exercise and nutrition knowledge, and 24-hour dietary recall. Posttests on the same measures were taken at the end of the intervention (8 months after the pretest).

At the beginning of the intervention, parents were invited to attend an orientation held at each school. The orientation included an opportunity to learn about the program and participate in selected tests (height, weight, skinfold, blood cholesterol, and dietary recall). One hundred parents chose to participate. Parents were asked to complete a medical history and consent-to-participate form. All materials were available in English, Spanish, Hmong, and Laotian. Participating parents received the results of their own tests as well as their children's. Families were asked to use this information to set activity goals to provide direction and motivation for behavior change. A family fitness scorecard was presented, and parents received directions on how points could be earned for physical activities and how to complete a physical activity log.  Family teams received weekly points for completing exercise and nutrition activities, which they recorded on their fitness scorecard and physical activity log. The research team recorded the points and posted them in the classrooms each week.  

Students in the control schools did not receive any additional instruction in nutrition and physical activity beyond that provided in their regular school curriculum. However, after the study ended, teachers and parents were provided with curriculum materials and home packets.

Effects of the Physical Activity and Nutrition for Health Intervention on Daily Total Fat Intake

• At the posttest, as measured by randomly selected 24-hour dietary recalls, the intervention schools showed a mean daily total fat intake of 57.05 grams, while control schools showed a mean of 64.68 grams (p<.05). Baseline means were 59.67 grams for the intervention group and 64.50 grams for the control group.

Effects of the Physical Activity and Nutrition for Health Intervention on Physical Fitness and Nutrition Knowledge

• At posttest, intervention schools had a mean exercise and nutrition knowledge score of 15.41, compared with a mean score of 13.43 for the control schools (p<.05).